The Peerless XLS12 has been my friend for many years
Well, two of them and the oldest is four years old to be exactly.

I started with the passive solution, and the most important experience is that you need TWO passive radiators.

After a year or so, I build an closed enclosure instead, and I have never looked back! They play music much better this way. Why I dont know for sure. Maybe its the group delay?

As I said; I use two of them, in 45L boxes and driven by two Hypex DS4.0 subamps. This amps has a one band eq and +6dB is what it takes to make it play flat.

And with four of these you could really play LOAD!

Here you can see some measurements I have done in my home cinema.
The first is one 830500 + 2x 830548 (425gr each) in a 49L box
The second is one 830500 in 45L closed box
And the third is the same as no two, with +6dB "bassboost"

Norcad - if you read back through the thread, you will see that the problem is that the 830547, 830548 and 830549 XLS passives have all been discontinued

And if you read my reply, you will see that I dont recommend them either
The XLS - 830500 is also discontinued, but still that is what this thread is about isnt it?

Im sorry for my bad english, but my point is that there are no reason to seek the world for some used passive radiators, the 830500 do (IMO) a better job alone. With four of them, the issue about eq and excursion limits doesnt exist.

I have tested the XLS 12 in four different boxes; with one passive radiator, with two passive radiators, in a BR, and closed.

And there is a reason why I now have two of them, and that they both is in a closed box.

Im sure that filipemacedo will be pleased with the result if he use them in 35L closed per driver. IF the xo point isnt to high, and some sort of eq is used in the bottom octave. BR kind of make up for the eq, but will (IMO) lack some SQ with music.

I will buy the 830500s (I still can buy them in Europe), but not the PRs. As I said before, I'll do some experimenting, including closed and vented, and then post the results. The x-over point is around 85Hz, and I will have to use some EQ (maybe LT).

I have tested the XLS 12 in four different boxes; with one passive radiator, with two passive radiators, in a BR, and closed.

And there is a reason why I now have two of them, and that they both is in a closed box.

Im sure that filipemacedo will be pleased with the result if he use them in 35L closed per driver. IF the xo point isnt to high, and some sort of eq is used in the bottom octave. BR kind of make up for the eq, but will (IMO) lack some SQ with music.

I'm using the XLS in my stereo set-up as well but as an additional sub.
It's a great woofer, but it does need lots of juice if mounted in a closed box, which I also think is best suited for this woofer.
I use 400 W with mine and a LT. You donīt need to tune it lower than 25 Hz ... that will be enough to pay 99.9 % of all available material ....
Take a look here: SubZero, a Peerless 12 inch XLS based subwoofer

As you also have found out, doing something to the room is essential ... and I really mean essential to get good bass.

I made my sup with a parametric EQ, to treat the most significant room mode, but I have found that this solution is no match for a propor passive room treatment (despite what all commercials will tell you about electronic or digital room eq).
Take a look here: Building a Home Theater and Listening Room

But would I go for 2 XLS'es for my front speakers? ..... not so sure .... I actually think I prefer vented speakers .... and the XLS is not suited for a vented design at all ......
Think I would actually go for a 60 l/24Hz vented design with dayton RSS 265 HF 4 .... only problem, it's a 4 ohm speaker .... but then again the XLS is more 5-6 ohm than 8!

Hi everyone,
Here I am again, but not with good news... The fact is that I couldn't get the 830500s because they have been discontinued and my supplier ran out of stock. Now it is OEM only with minimum qty of 250 units...
I have the option for 4x 835017, 12’’ XXLS Alu-cone subwoofer, which I think is also a good sub, but needs a little more “space”! I think I’ll use one for each main speaker, and two additional subs, placed along the opposite wall.
And yes, I found the room-treatment stuff quite interesting, along with the links Baldin referred, but I haven’t done anything yet. Life is hard…
Any suggestions regarding the 835017?
I promise I’ll post the results and simulations soon, as long as I don’t change my mind…